Department of Nuclear Medicine, University Hospital Essen, Essen, Germany.
German Cancer Consortium, partner site Essen, Essen, Germany.
J Nucl Med. 2023 Mar;64(3):372-378. doi: 10.2967/jnumed.122.264342. Epub 2022 Sep 22.
We analyzed the diagnostic performance of prostate-specific membrane antigen (PSMA) PET/CT and the dosimetry, efficacy, and safety of Lu-PSMA-617 radioligand therapy (RLT) in salivary gland malignancies (SGMs). We identified 28 SGM patients with PSMA PET/CT from our database. CT and PSMA PET/CT images were evaluated separately by 3 masked readers in joint reading sessions. Pathologic findings were grouped into 6 TNM regions, and lesion-based disease extent was classified as no disease ( = 1, 4%), unifocal ( = 2, 7%), oligometastatic ( = 9, 32%), multifocal ( = 3, 11%), or disseminated ( = 13, 47%). For each region, the SUV of the lesion with the highest uptake was measured and the visual PSMA expression score was evaluated on a per-patient basis using PROMISE criteria. The association between PSMA expression and clinical and histopathologic markers was tested using the Student test. Five patients underwent PSMA RLT with intratherapeutic dosimetry. Response was assessed using RECIST 1.1, and adverse events were graded according to version 5.0 of the Common Terminology Criteria for Adverse Events. Compared with CT, PSMA PET/CT demonstrated additional metastatic lesions in 11 of 28 (39%) patients, leading to upstaging of TNM and lesion-based disease extent in 3 (11%) and 6 (21%) patients, respectively. PSMA PET/CT detected CT-occult local tumor, regional lymph nodes, nonregional lymph nodes, and bone metastases in 1 (4%), 4 (14%), 2 (7%), and 4 (14%) patients, respectively; no additional lesions were detected in the other predefined regions. PSMA expression level was higher than liver in 6 patients (25%). A significantly higher SUV was observed in male than female patients (15.8 vs. 8.5, = 0.007) and in bone than lung lesions (14.2 vs. 6.4, = 0.006). PSMA RLT was discontinued after 1 cycle in 3 of 5 patients because of insufficient tumor doses. No adverse events of grade 4 or higher occurred. In SGMs, PSMA PET/CT demonstrated a superior detection rate and led to upstaging in about one third of patients when compared with CT. The male sex and the presence of bone metastases were associated with significantly higher PSMA expression. PSMA RLT was well tolerated, but most patients did not have more than 1 cycle because of insufficient tumor doses.
我们分析了前列腺特异性膜抗原（PSMA）PET/CT 的诊断性能，以及 Lu-PSMA-617 放射性配体治疗（RLT）在唾液腺癌（SGM）中的剂量学、疗效和安全性。我们从数据库中确定了 28 名 SGM 患者进行 PSMA PET/CT 检查。3 位蒙面读者在联合阅读会议上分别对 CT 和 PSMA PET/CT 图像进行评估。病理发现分为 6 个 TNM 区域，根据病变范围将病变分为无疾病（ = 1，4%）、局限性（ = 2，7%）、寡转移（ = 9，32%）、多灶性（ = 3，11%）或播散性（ = 13，47%）。对于每个区域，测量摄取最高的病变的 SUV，并使用 PROMISE 标准基于每位患者评估视觉 PSMA 表达评分。使用学生 t 检验测试 PSMA 表达与临床和组织病理学标志物之间的关联。5 名患者接受了 PSMA RLT 治疗，并进行了治疗内剂量测定。使用 RECIST 1.1 评估反应，并根据不良事件通用术语标准 5.0 分级。与 CT 相比，PSMA PET/CT 在 28 名患者中的 11 名（39%）中发现了额外的转移性病变，导致 TNM 和病变范围分别在 3 名（11%）和 6 名（21%）患者中升级。PSMA PET/CT 在 1 名（4%）患者中检测到 CT 隐匿性局部肿瘤、区域淋巴结、非区域淋巴结和骨转移；在 4 名（14%）、2 名（7%）和 4 名（14%）患者中分别检测到 CT 隐匿性局部肿瘤、区域淋巴结、非区域淋巴结和骨转移；在其他预定区域未检测到额外病变。PSMA 表达水平在 6 名患者（25%）中高于肝脏。男性患者的 SUV 明显高于女性患者（15.8 比 8.5， = 0.007），骨病变的 SUV 明显高于肺病变（14.2 比 6.4， = 0.006）。由于肿瘤剂量不足，5 名患者中的 3 名在 1 个周期后停止了 PSMA RLT。没有发生 4 级或更高的不良事件。在 SGM 中，与 CT 相比，PSMA PET/CT 的检测率更高，约三分之一的患者出现了分期升级。男性和骨转移与 PSMA 表达显著升高有关。PSMA RLT 耐受性良好，但由于肿瘤剂量不足，大多数患者的治疗周期不足 1 个。
